That bell they clang on Wall Street at precisely the same time would come in handy for the NFL on Tuesday at 4 p.m. EDT.

That's when hundreds of unrestricted NFL free agents officially become free, and can sign with new teams.

For the second year, UFAs and their agents have been permitted to negotiate with prospective new teams since mid-day Saturday. This pre-negotiation window of sorts is to allow clubs' GMs to, well, officially tamper.

Indeed as the league specifies, clubs are "permitted to contact and enter into negotiations with" players' agents only. No contract can be drawn up, nor can teams talk with the players themselves, nor make any travel arrangements with them.

As is always the case, just how active or aggressive a team is in free agency depends on three factors:

1. ITS PHILOSOPHY. Some clubs just don't believe in jostling at the get-go and overpaying for big-name free agents who might or might not pan out. They prefer to wait for the second wave of free agents next week or, more likely, for the bargains that are always out there by Week 3.

2. CAP ROOM. Every team has at least $10 million of extra cap space this year, as the team cap rises in 2014 to $133 million, from $123 million. The Raiders reportedly have the most money to play with -- some $64 million, followed by the Jags ($56M), Browns ($49M), Vikings ($40M), Colts ($37M) and Dolphins ($34M). At the other end are the Cowboys, with less than $1M of free space, at least as of Monday morning.

3. ROOKIES ARE CHEAPER. Say a team is desperate to upgrade at wide receiver. It so happens that this year's draft class is deeply stocked with wideouts, so many such teams might eschew the bidding wars for veteran free agents and just wait until May's draft. Because rookies aren't just younger, they're wayyyyyy cheaper than veterans.

Below are QMI Agency's rankings of the top available free agents -- barring last-minute re-signings with their current teams, and excluding any other big-name, big-contract veterans still to be dumped and thus set free by Tuesday afternoon:

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OFFENCE, OVERALL TOP 10

1. LT Eugene Monroe (Baltimore)

After the Ravens acquired him in a trade from Jags, instantly improved sieve of an OL. Best of several excellent left tackles available.

2. LT Anthony Collins (Cincinnati)

According to analytics website ProFootballFocus.com, the Bengal did not allow a single QB pressure, let alone sack, in '13. Sign him up!

3. LT Branden Albert (Kansas City)

Chiefs' stalwart widely reported to be coveted by Dolphins, who are overhauling entire OL. This 29-year-old's a good place to start.

4. QB Michael Vick (Philadelphia)

Still has plenty of arm, and hasn't slowed much. But is he a beat-up turnover machine? Maybe. At the very least he'd be a helluva backup.

5. LT Jared Veldmeer (Oakland)

Most observers were shocked the Raiders did not franchise-tag him. Only 26 and a stud. Cardinals reported to be hot after him.

6. WR Golden Tate (Seattle)

Trusty hands, relentless competitor, great locker-room addition. Can return punts too. Not a field-stretcher, but only 25. Patriots?